Abandoned Mine Modeling to Aid in Remediation -- Sampling by the USGS in Cement Creek, a tributary to the Animas River in southwestern Colorado, has identified both distinct and dispersed sources of metal-rich, acidic water to the stream. Water quality in Cement Creek is affected by inflows of metal-rich and acid water related to abandoned mines and naturally occurring conditions along its entire length of approximately 10 miles. The poor water quality adversely affects aquatic life, and no fish are present. USGS scientists are working in conjunction with the Bureau of Land Management to identify distinct sources of poor quality water that might be amenable to cleanup, and are using computer simulations to help predict the effects of different remediation scenarios and account for the effects of the dispersed contamination. Understanding the potential effects of different cleanup approaches can help the BLM determine the most cost effective solutions to water-quality problems associated with drainage from abandoned mines. Join USGS scientist Katie Walton-Day on Wednesday, November 15 at 8:10 a.m., Room B3 to learn more.

Accurate and User-friendly Ground Water Models? -- Ground-water models are used to evaluate whether sources of pollution are likely to contaminate water wells used to supply water to communities and industry. Because of sparse data, inaccessibility of the subsurface, problems that obscure the relation between field measurements and simulated quantities, and the urgent needs of society to make important water-resource decisions, ground-water modeling presents one of the most challenging modeling situations in the natural sciences and engineering. The USGS, in cooperation with the U.S. Department of Energy and the U.S. Department of Defense, has been working to develop these two approaches of making ground-water models more reliable. The USGS recently improved its already very widely used ground-water model, MODFLOW, to include the most recent advances in comparing computed and measured values and displaying these comparisons in standardized, easy to understand ways. MODFLOW now also allows geologic information to be more easily included in a ground-water model. MODFLOW is available for free to all users at http://water.usgs.govhttp://water.usgs.gov -- click on "software" under Technical Resources, then click "Ground Water" and then "MODFLOW-2000". USGS scientist Mary Hill will demonstrate MODFLOW on Wednesday, November 15 at 8:45 a.m., Room A4.

Abandoned Mining Pits in Nevada -- may contain high levels of arsenic and other toxic elements. Laurie Balistrieri, a USGS researcher who has analyzed the waters of the Dexter Pit Lake near Tuscarora, Nev., will report on her findings at 9:45 a.m., Wednesday, November 15, in Room B7.

Why Engineered Alluvial Rivers Flood-- Alluvial rivers, like the Missouri River, highly altered by humans, still experience extreme floods, such as the Midwest Flood of 1993. The effects of these floods, however, vary greatly, depending on many geological and man-induced factors. Using state-of-the-art technology, USGS scientist Dr. Robert Jacobson studies such rivers, focusing on processes that affect large- and small-scale changes, and will be presenting his research on Wednesday, November 16 at 10:40 a.m., Hall B. His work addresses fundamental science issues of how humans and rivers interact; issues critical to both. Visit the web at: http://infolink.cr.usgs.gov/science/habitats/index.html

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Mercury Contamination; Legacy of the Gold Rush -- Thousands of pounds of mercury and other chemicals that were used to separate gold from other minerals during the latter half of the 19th century, are still present in California waterways. Wednesday, November 15, at 10:50 a.m., in Room B7, Mike Hunerlach will describe the mercury-laden sediments in streams such as the Bear River and South Yuba Rivers and the accumulation of methylmercury in the fish of those streams.

How Has Mining Affected Certain Biota and Human Populations in Colorado? -- The Animas watershed, located in the San Juan Mountains of southern Colorado, is a spectacularly beautiful river valley that ranges from the high elevation peaks around Silverton to the high plains around Durango. The Silverton-Durango narrow gauge railroad traverses through the heart of this study area, and in fact provided one of the platforms for collection of samples. This study is part of a multidisciplinary approach to understand the impacts of mining activities in the San Juan Mountains on the downstream aquatic biota of the Animas River and on the human population throughout the river valley. Among other factors, this study recovered an extremely sparse fossil record, indicating that the physical-chemical parameters of the Animas watershed have been harsh even before mining activities impacted the environments. USGS scientist Elisabeth Brouwers will share the results of this research in a poster session on Wednesday, November 16 from 8 a.m to noon.

The Sediments of San Pablo Bay -- a sub-estuary of San Fraincisco Bay, contain higher than normal levels of mercury – a legacy of the hydraulic mining debris that washed into the bay during the 1800s. Research on this problem will the topic of a presentation by Mark Marvin-Dipasquale, at 2 p.m., Wednesday, November 15, in Room B7.

Mercury Vapor and Dust – that were released during the "roasting" of ores, contaminate surface areas throughout the west. Add acid mine drainage and you have great environmental impacts and challenges. At 4:30 p.m., Wednesday, November 15, Jim Rytuba will present aspects of the environmental challenge in dealing with mercury and other chemicals or elements that were introduced into western streams during gold mining activities of the late 19th century.

Mercury in Sediments of Lake Tulane, Florida – appear to have been carried there with dust from North Africa, thousands of years ago. Terry Edgar will describe the amount and significance of these mercury deposits at 3:15 p.m., Wednesday, November 15, in Room B7.

Mercury Contamination in Philippines -- Since 1995, high mercury contents have been found in blood samples from more than 20 people living near the Palawan Quicksilver mine, Philippines. The USGS is working with biomedical researchers from the U.S. and the Philippines to determine the source and pathway of mercury to humans in this area. USGS scientist John Gray will offer more details about the joint research on Wednesday, November 15 at 4:45 p.m., Room B7.

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